The present disclosure relates to image forming apparatuses such as copier, printers, facsimile machines, and multifunction peripherals functioning as more than one of those devices. More particularly, the present disclosure relates to a method of expelling air inside an image forming apparatus out of it with a fan.
In an image forming apparatus relying on electrophotography, toner is attached to an electrostatic latent image formed on a photosensitive member to form a toner image, then the toner image is transferred to paper, and then the toner image on the paper is fused by a fusing device.
In a fusing device of a heating type which fuses a toner image to paper by heating the paper, the heating can cause release of ultrafine particles (UFPs) from inside to outside the image forming apparatus. Today, with increasing consciousness of environmental issues, release of ultrafine particles (UFPs) into the environment is sought to be suppressed. Ultrafine particles (UFPs) refers to, out of suspended particulate matter, particles with diameters of 100 nm or less. It has come to be known that ultrafine particles (UFPs) arise chiefly from silicone rubber used as an elastic layer in a heating roller or the like. Specifically, when silicone rubber is heated to over a predetermined temperature, low-molecular siloxanes are produced, which spread as ultrafine particles (UFPs).
Solutions are offered by some known technologies for suppressing release of ultrafine particles (UFPs) out of image forming apparatuses. For example, an image forming apparatus is known which is provided with a louver for changing the size of the opening of an exhaust port, wherein the opening and closing of the louver is controlled based on the temperature sensed by a temperature sensor that senses the temperature around a fusing roller. In this image forming apparatus, a filter for collecting ultrafine particles (UFPs) and the like is provided in the exhaust port to minimize release of ultrafine particles (UFPs) and the like out of the image forming apparatus, and when the temperature sensed by the temperature sensor exceeds 170° C., the louver is automatically closed to prevent release of ultrafine particles (UFPs), ozone, toner and other particles, etc. out of the image forming apparatus.